Imaging with two-axis micromirrors

We demonstrate a means of creating a digital image by using a two axis tilt micromirror to scan a scene. For each different orientation we extract a single grayscale value from the mirror and combine them to form a single composite image. This allows one to choose the distribution of the samples, and so in principle a variable resolution image could be created. We demonstrate this ability to control resolution by constructing a voltage table that compensates for the non-linear response of the mirrors to the applied voltage.Comment: 8 pages, 5 figures, preprin

Εφαρμογή Απεικόνισης Κίνησης σε Πραγματικό Χρόνο ως Κοινωνικό Δίκτυο

Η ανάγκη της επικοινωνίας αποτελεί πρωταρχική επιδίωξη των ανθρώπων στις οργανωμένες κοινωνίες. Η αλματώδης άνθηση των τηλεπικοινωνιών τις τελευταίες δεκαετίες και η συνακόλουθη παραγωγή προϊόντων και υπηρεσιών, που στοχεύουν στην κάλυψη του πλήθους των επικοινωνιακών αναγκών είναι εντυπωσιακή. Εντούτοις, το εύρος των δυνατοτήτων που παρέχει η τεχνολογία μέσω των παραδοσιακών δικτύων (τηλέφωνο, sms, κ.α.) αλλά και των μέσων κοινωνικής δικτύωσης (chatting μέσω Facebook, κ.α.) αδυνατούν να εξαλείψουν τους συχνούς επικοινωνιακούς «θορύβους». Η έλλειψη συνεπούς, έγκαιρης και αποτελεσματικής συνεννόησης για το ακριβές σημείο συνάντησης και τον ακριβή χρόνο, καθυστερήσεις και παραλείψεις, όταν το ζητούμενο είναι η φυσική επαφή, είναι μόνο μερικοί από αυτούς. Η αναποτελεσματικότητα της επικοινωνίας δύναται να περιοριστεί δραστικά από μία δικτυακή εφαρμογή, η οποία θα απεικονίζει σε πραγματικό χρόνο, μέσω ενός διαδραστικού χάρτη, την ακριβή κίνηση των αλληλοεπιδρώντων και θα παρέχει δυναμικές πληροφορίες υπολειπόμενου χρόνου και απόστασης σε σχέση με το σημείο συνάντησης που έχει οριστεί. Ουσιαστικά, μια τέτοια εφαρμογή θα αποτελεί ένα κοινωνικό δίκτυο με ολοκληρωμένες δυνατότητες αλληλεπίδρασης των χρηστών του. Τέλος, πέραν της αποτελεσματικής συνάντησης των χρηστών, η εφαρμογή θα πρέπει να συλλέγει τα δεδομένα κίνησης του κάθε χρήστη με σκοπό τη διατήρηση ιστορικότητας, την ανάλυση και τη βελτιστοποίηση των προτιμήσεών του. Η παρούσα διπλωματική εργασία έχει ως σκοπό την ανάπτυξη μιας καινοτόμας εφαρμογής για την εξυπηρέτηση μιας ανθρώπινης ανάγκης. Στο πλαίσιο της εργασίας αναλύεται πως διαπιστώθηκε αυτή η ανάγκη και πως δύναται να καλυφθεί με την εν λόγω εφαρμογή. Κατόπιν ενδελεχούς έρευνας που πραγματοποιήθηκε, διαπιστώθηκε ότι το τρέχον φάσμα τεχνολογιών και υπηρεσιών δεν είναι σε θέση να προσεγγίσει τις παρεχόμενες λειτουργίες της εφαρμογής. Παράλληλα, εξετάστηκαν και αναλύθηκαν οι εκάστοτε προσφερόμενες τεχνολογίες και περιβάλλοντα προϋπαρχόντων συναφών υπηρεσιών, έτσι ώστε να μεγιστοποιηθεί η αποτελεσματικότητα και η αποδοτικότητα της εφαρμογής με τελικό στόχο την πλήρη εκμετάλλευση της από το χρήστη, καθιστώντας την απλή και φιλική. Μέσα από την παρουσίαση της εφαρμογής επεξηγούνται τα πλήρη οφέλη της καθώς αναλύεται εκτενώς ολόκληρος ο σχεδιασμός της εφαρμογής και ο επιθυμητός και τελικός στόχος λειτουργίας της. Πάνω σε αυτήν την ανάλυση βασίζεται ο καθορισμός των απαιτήσεων και η χρήση κατάλληλης τεχνολογικής υποδομής τελευταίας γενιάς για την ολοκληρωτική υποστήριξη και ορθή λειτουργία της. Στη συνέχεια, αναπτύσσεται διεξοδικά ο τρόπος λειτουργίας των κύριων δυνατοτήτων της εφαρμογής καθώς και των επιμέρους λειτουργιών της. Επίσης, παρατίθενται εικόνες χρήσης της εφαρμογής για την πλήρη κατανόηση του φάσματος των δυνατοτήτων της. Τέλος, αξιολογείται η αποδοτικότητα της εφαρμογής, οι παρεχόμενες υπηρεσίες, εξετάζονται πιθανές βελτιώσεις και γίνεται αναφορά σε μελλοντικές προσθήκες για την αναβάθμιση της εφαρμογής.The need of communication between people constitutes a primary pursuit in organized societies. The swift growth of telecommunications in last decades, followed by the generation of products and services that are targeting to cover the telecommunications needs, is revealing. However, the possibilities that technology offers through the traditional networks (phone, sms, etc.) and social networks (chatting by Facebook, etc.), cannot eliminate the frequent communication “noises”. The absence of timely, consistent and effective arrangement for the specific spot of meeting and time, delays and failures, when the point is the physical contact, are only some of them. The inefficiency of communication could dramatically be improved by an internet application which would illustrate in real time, through an interactive map, the specific traffic of people and would provide dynamic information of the remaining time and distance relative to the meeting point that has been settled. Essentially, the application will be a social network with full operations of interactions between the users. Besides the effective meeting between the users, the application should collect data of movement of every user in order to store his history that will be analyzed for the improvement of his preferences. The current thesis is the development of an innovative application that will serve a human need. In the thesis we explain how this need has been identified and how it could be covered by the application that has been developed. After deep search, we have concluded that the current range of technologies and services cannot reach the potentials and the functions of our app. Meantime, many similar preexisted applications and services have been examined in order to locate and verify their weaknesses and shortcomings, so that our new product would be simple and friendly and of course effective and efficient. Through the presentation of the devolved application we explain all the benefits while we thoroughly describe the application design and our desirable goal. The definition of our requirements as well as the use of the proper technology for the flawless operation and support of our application is based on the aforementioned analysis. Next, we present the main and the secondary functionality of our applications`. We include images that demonstrate how the application can be used in order to illustrate in a better way the range of its potential. Finally, we evaluate the efficiency of the application and the provided services and we examine possible improvements and updates for its enhancement

A novel approach to programmable imaging using MOEMS

New advancements in science are frequently sparked by the invention of new instruments. Possibly the most important scientific instrument of the past fifty years is the digital computer. Among the computers many uses and impacts, digital imaging has revolutionized images and photography, merging computer processing and optical images. In this thesis, we merge an additional reconfigurable micro-mechanical domain into the digital imaging system, introducing a novel imaging method called Programmable Imaging. With our imaging method, we selectively sample the object plane, by utilizing state-of-the-art Micro-Optical-Electrical-Mechanical Systems (MOEMS) of mirror arrays. The main concept is to use an array of tiny mirrors that have the ability to tilt in different directions. Each mirror acts as an “eye” which images a scene. The individual images from each mirror are then reassembled, such that all of the information is placed into a single image. By exact control of the mirrors, the object plane can be sampled in a desired fashion, such that post-processing effects, such as image distortion and digital zoom, that are currently performed in software can now be performed in real time in hardware as the image gets captured. It is important to note that even for different sampling or imaging functions, no hardware components or settings are changed in the system.In this work, we present our programmable imaging system prototype. The MOEMS chipset used in our prototype is the Lucent LambdaRouter mirror array. This device contains 256 individually-controlled micro-mirrors, which can be tilted on both the x and y axes ±8o. We describe the theoretical model of our system, including a system model, capacity model, and diffraction results. We experimentally prototype our programmable imaging system using both a single mirror, followed by multiple mirrors. With the single mirror imaging, we explore examples related to single projection systems and give details of our required mirror calibration. Using this technique, we show mosaic images, as well as images in which a single pixel was extracted for every mirror tilt. Using this single pixel approach, the greatest capabilities of our programmable imaging are realized. When using multiple mirrors to image an object, new features of our system are demonstrated. In this case, the object plane can be viewed from different perspectives. From these multi-perspective images, virtual 3-D images can be created. In addition, stereo depth estimation can be performed to calculate the distance between the object and the image plane. This depth measurement is significant, as the depth information is taken with only one image from only one camera.Ph.D., Electrical Engineering -- Drexel University, 200

Interval training induces clinically meaningful effects in daily activity levels in COPD

Mounting evidence suggests that daily activity levels (DAL) in patients with chronic obstructive pulmonary disease (COPD) are markedly low compared with healthy age-matched individuals and are associated with poorer health status and prognosis [1]. COPD severity negatively impacts on DAL since patients with low DAL experience greater ventilatory, central haemodynamic and peripheral muscle oxygenation constraints during activities of daily living when compared with more physically active counterparts [2, 3]. Although exercise training as part of pulmonary rehabilitation has shown to mitigate the aforementioned physiological constraints [4], there is no evidence of clinically meaningful improvements in DAL following pulmonary rehabilitation [5] as manifested by a mean increase of at least 1000 steps·day−1 [6]. This has been attributed to methodological shortfalls, such as lack of adequately controlled studies, small sample size, short duration of pulmonary rehabilitation programmes, application of activity monitors non-validated for COPD patients [5] and insufficient exercise intensities to induce true physiological training effects. Interval exercise training has been shown to allow application of intense loads to peripheral muscles that induce substantial physiological effects manifested by mitigation of respiratory and central haemodynamic limitations and partial restoration of peripheral muscle dysfunction in patients with diverse COPD severity [7, 8]. In this context, it is reasoned that application of this training modality would allow transfer of the aforementioned physiological benefits into clinically meaningful improvements in DAL [2, 3]. Accordingly, the purpose of this randomised controlled study was to investigate the effect of a 12-week high-intensity interval exercise training programme in DAL in addition to usual care in patients with COPD

Limitation in tidal volume expansion partially determines the intensity of physical activity in COPD

open8In patients with Chronic Obstructive Pulmonary Disease (COPD) reduced levels of daily physical activity are associated with the degree of impairment in lung, peripheral muscle and central hemodynamic function. There is however, limited evidence as to whether limitations in tidal volume expansion also, importantly determine daily physical activity levels in COPD. Eighteen consecutive COPD patients [9 active (FEV1:1.59±0.64 liters) with an average daily movement intensity >1.88 m/sec(2) and 9 less active patients (FEV1:1.16±0.41 liters) with an average intensity <1.88 m/sec(2)] underwent a 4-min treadmill test at a constant speed corresponding to each individual patient's average movement intensity, captured by a triaxial accelerometer during a preceding 7-day period. When chest wall volumes, captured by Optoelectronic Plethysmography, were expressed relative to comparable levels of minute ventilation (ranging between 14.5±4.3 to 33.5±4.4 liters/min), active patients differed from the less active ones in terms of the lower increase in end-expiratory chest wall volume (by 0.15±0.17 versus 0.45±0.21 liters), the greater expansion in tidal volume (by 1.76±0.58 versus 1.36±0.24 liters) and the larger inspiratory reserve chest wall volume (IRVcw: by 0.81±0.25 versus 0.39±0.27 liters). IRVcw (r(2)=0.420), expiratory flow (r(2) change=0.174) and Borg dyspnoea score (r(2) change=0.123) emerged as the best contributors accounting for 71.7\% of the explained variance in daily movement intensity. COPD patients exhibiting greater ability to expand tidal volume and to maintain adequate inspiratory reserve volume tend to be more physically active. Thus, interventions aiming at mitigating restrictions on operational chest wall volumes are expected to enhance daily physical activity levels in COPD.openE. A. Kortianou;A. Aliverti;Z. Louvaris;M. Vasilopoulou;I. Nasis;A. Asimakos;S. G. Zakynthinos;I. VogiatzisE. A., Kortianou; Aliverti, Andrea; Z., Louvaris; M., Vasilopoulou; I., Nasis; A., Asimakos; S. G., Zakynthinos; I., Vogiatzi

Texture Analysis of Cardiovascular Magnetic Resonance Cine Images differentiates etiologies of left ventricular hypertrophy

BACKGROUND: Textural analysis (TA) shows promise as radiological biomarker. The use of native TA in the field of cardiology is unproven. We hypothesized that Cardiovascular Magnetic Resonance pre-contrast bSSFP cine images could be analysed using TA software; TA features would differentiate different aetiologies of disease causing increased myocardial wall thickness (left ventricular hypertrophy {LVH}) and indicate the severity of myocardial tissue abnormality. METHOD: A mid short axis pre-contrast cine frame of 216 cases (50 hypertrophic cardiomyopathy (predominantly LVOTO sub type) (HCM), 52 cardiac amyloid (predominantly AL sub-type) (CA), 68 aortic stenosis (AS), 15 hypertensive with LVH (HTN+LVH) and 31 healthy volunteers (HV)) underwent CMRTA using TexRAD (TexRAD Ltd, Cambridge, UK). Among HV, 16/ 31 were scanned twice to form a test-retest reproducibility cohort. CMRTA comprised a filtration-histogram technique to extract and quantify features using 6 parameters. RESULTS: Test-retest analysis in HV showed a medium filter (3mm) was the most reproducible (intra-class correlation of 0.9 for kurtosis and skewness and 0.8 for mean and SD). Disease cohorts were statistically different (p<0.001) to health for all parameters. Pair wise comparisons of CMRTA parameters showed kurtosis and skewness consistently significant in ranking degree of difference from HV (greatest to least); CA, HCM, LVH+HTN, AS (p<0.001). Similarly mean, SD, entropy and mean positive pixel (MPP) were consistent in ranking degree of difference from HV; HCM, CA, AS and HTN+LVH. CONCLUSION: Radiomic features of bSSFP CMR data sets, derived using TA, show promise in discriminating between aetiologies of LVH

Morphogenesis of myocardial trabeculae in the mouse embryo

Formation of trabeculae in the embryonic heart and the remodelling that occurs prior to birth is a conspicuous, but poorly understood, feature of vertebrate cardiogenesis. Mutations disrupting trabecular development in the mouse are frequently embryonic lethal, testifying to the importance of the trabeculae, and aberrant trabecular structure is associated with several human cardiac pathologies. Here, trabecular architecture in the developing mouse embryo has been analysed using high-resolution episcopic microscopy (HREM) and three-dimensional (3D) modelling. This study shows that at all stages from mid-gestation to birth, the ventricular trabeculae comprise a complex meshwork of myocardial strands. Such an arrangement defies conventional methods of measurement, and an approach based upon fractal algorithms has been used to provide an objective measure of trabecular complexity. The extent of trabeculation as it changes along the length of left and right ventricles has been quantified, and the changes that occur from formation of the four-chambered heart until shortly before birth have been mapped. This approach not only measures qualitative features evident from visual inspection of 3D models, but also detects subtle, consistent and regionally localised differences that distinguish each ventricle and its developmental stage. Finally, the combination of HREM imaging and fractal analysis has been applied to analyse changes in embryonic heart structure in a genetic mouse model in which trabeculation is deranged. It is shown that myocardial deletion of the Notch pathway component Mib1 (Mib1(flox/flox); cTnT-cre) results in a complex array of abnormalities affecting trabeculae and other parts of the heart.This work was supported by funding to TJM from the Medical Research Council (U117562103); to JCM by the Higher Education Funding Council for England; to JLdlP and GL by grants SAF2010-17555 and SAF2013-45543-R from the Spanish Ministry of Economy and Competitiveness (MINECO); and to GC by a research fellowship at the University College London Biomedical Research Centre from the UK National Institutes of Health Research Cardiometabolic Programme.S

Quantitative planar and volumetric cardiac measurements using 64 mdct and 3t mri vs. Standard 2d and m-mode echocardiography: does anesthetic protocol matter?

Cross‐sectional imaging of the heart utilizing computed tomography and magnetic resonance imaging (MRI) has been shown to be superior for the evaluation of cardiac morphology and systolic function in humans compared to echocardiography. The purpose of this prospective study was to test the effects of two different anesthetic protocols on cardiac measurements in 10 healthy beagle dogs using 64‐multidetector row computed tomographic angiography (64‐MDCTA), 3T magnetic resonance (MRI) and standard awake echocardiography. Both anesthetic protocols used propofol for induction and isoflourane for anesthetic maintenance. In addition, protocol A used midazolam/fentanyl and protocol B used dexmedetomedine as premedication and constant rate infusion during the procedure. Significant elevations in systolic and mean blood pressure were present when using protocol B. There was overall good agreement between the variables of cardiac size and systolic function generated from the MDCTA and MRI exams and no significant difference was found when comparing the variables acquired using either anesthetic protocol within each modality. Systolic function variables generated using 64‐MDCTA and 3T MRI were only able to predict the left ventricular end diastolic volume as measured during awake echocardiogram when using protocol B and 64‐MDCTA. For all other systolic function variables, prediction of awake echocardiographic results was not possible (P = 1). Planar variables acquired using MDCTA or MRI did not allow prediction of the corresponding measurements generated using echocardiography in the awake patients (P = 1). Future studies are needed to validate this approach in a more varied population and clinically affected dogs

Using Australia’s National Data Linkage Demonstration Project (NDLDP) to improve cardiac care: Towards a national, whole-of-population linked data resource for evidence-informed health policy

Introduction In Australia, the Commonwealth, State and Territory governments are each responsible for specific aspects of health care. Historically, cross-jurisdictional health data have not been linked routinely, resulting in significant blind spots in our understanding of the interplay between hospital and primary care, a major impediment to evidence-informed health policy. Objectives and Approach In December 2016, the Australian Health Ministers’ Advisory Council approved the NDLDP, to establish the value of national linked data to inform health planning and policy. The Australian Institute of Health and Welfare (AIHW) linked five years of hospital, emergency department, pharmaceutical dispensing, medical services claims and mortality data for Australia’s two most populous states (New South Wales and Victoria). The Victorian Agency for Health Innovation (VAHI) is leading the ‘Delivering better cardiac outcomes: Primary, specialist and hospital care’ project to demonstrate the value of the collection in identifying evidence-practice gaps and driving change in cardiac care. Results The NDLDP combined data for over 10 million individuals with over 7 billion records of health transactions, utilising a new strategy for confidentialising dates to protect patient privacy. The NDLDP is governed by a Steering Committee; the AIHW is the data custodian approving outputs from analyses within a secure host environment. VAHI established a Project Steering Committee to oversee roll-out, governance and capacity building of the approved cardiac project. The VAHI project was instigated by evidence that best-practice pharmacological treatments for cardiac care are underutilised in Australia, but with no quantification of the population-level extent of this gap. The project quantified significant variations and underuse of post-discharge pharmacological care for patients admitted to hospital with key cardiac conditions, including atrial fibrillation and acute myocardial infarction. Conclusion/Implications This collaboration between government, clinical networks and academic researchers demonstrated this novel data linkage can enable evaluation of patient care pathways across both hospital and community-based services. These linked data resources provide essential information to investigate variation in care in Australia and improve care integration in cardiac care and beyond